Question

6. An optician prescribe a lens of
power +2.5 D. The lens is having
focal length_cm.
O
Convex lens, +0.4
Concave lens, +0.4
O
Convex lens, +40
Concave lens +40​

Answer 1

we know that power P=2.5D

we know that power P=2.5D P= f1

we know that power P=2.5D P= f1 f= 2.51 =0.4m=40cm

we know that power P=2.5D P= f1 f= 2.51 =0.4m=40cmSince the focal length of lens is positive so it is a convex lens. It is a converging lens

mark as BRAINLEST please.

Answer 2

If the power is +ve then it is convex lens

answer c part

Explanation:

Now P = +2.5 D

f =

using formula; P = 100/ f

f = 100/ 2.5

then; f = +40cm